School of Earth Sciences and Engineering Hohai University Nanjing 210024 ChinaCollege qf Geology Engineering and Geomantic Chang''an University Xi''an 710054 China;
School of Earth Sciences and Engineering Hohai University Nanjing 210024 China;
College qf Geology Engineering and Geomantic Chang''an University Xi''an 710054 China;
School of Earth Sciences and Engineering Hohai University Nanjing 210024 China;
GNSS-IR; terrain retrieval; signal-to-noise ratio; reflector height;